StairPlan: Stair Calculator

Rise, Run, Stringer & Tread

Only for iPhone

Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.

iPhone

Calculate stair stringer cuts in seconds. IRC R311.7 compliant. Export PDF cut diagrams. 100% offline. Lifetime purchase available. What does StairPlan do? Calculates stringer length, riser height, tread depth, and pitch angle for any staircase. Enter total rise and tread depth, get instant results plus an IRC R311.7 compliance check. Is my data private? 100% offline. Nothing leaves your iPhone. No accounts, no analytics, no ads, no tracking. How do I get started? 1. Enter total rise (floor to floor height) 2. Enter desired tread depth (default 10 inches) 3. Read off riser count, riser height, stringer length, and pitch angle What can I do with it? - Real-time stair calculations with imperial fractions or metric - IRC R311.7 compliance warnings (riser height, tread depth, max flight, sum rule) - Save unlimited stair projects with custom names and notes - Export scale PDF cut diagrams to print and tape to your wall - Side view visualization updates as you type - Reference section with IRC code, formulas, and cutting instructions What units does it support? Imperial (feet and inches with fractions to 1/16) and Metric (millimeters and centimeters). Will the PDF print at actual size? Yes. PDF output uses 1 inch = 72 points so the cut diagram prints at true scale on letter or A4 paper. Tape it to your stringer board and trace. Who is this for? Carpenters, finish carpenters, deck builders, renovation contractors, and DIY homeowners building porch steps, deck stairs, or interior staircases. How much does it cost? 3-day free trial, then $1.99/week, $4.99/month, $29.99/year, or $79.99 lifetime. Terms of Use: https://taxlite.net/stair_stringer_calc/terms.html Privacy Policy: https://taxlite.net/stair_stringer_calc/privacy.html

Ratings & Reviews

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Big V1.1 update — built around how real carpenters work. NEW STAIR TYPES - L-shaped, U-shaped, and winder stairs alongside straight - Per-flight stringer + run breakdown - IRC R311.7.5.2.1 walkline tread check at 12-inch radius GLOBAL CODE COMPLIANCE - Switch between US IRC, Canada NBC (OBC mirror), UK Approved Doc K, and Australia NCC 2022 - Region-specific thresholds for max riser, tread, headroom, pitch, and landing HEADROOM + FLOOR FINISH COMPENSATION - Optional ceiling height input flags low headroom - Top / bottom finish thickness inputs ensure equal risers AFTER flooring AR MEASURE (LiDAR aware) - Two-tap distance measurement straight into Total Rise - LiDAR-equipped iPhones get +/-1 cm accuracy 3D PREVIEW - SceneKit isometric view alongside the 2D side elevation - Drag to orbit, pinch to zoom EXPORTS + MATERIALS - Per-project Bill of Materials added as PDF page 2 (lumber feet, treads, risers, total cost) - DXF (CAD) and SVG (vector) export alongside PDF - 1:N integer scale picker auto-snaps to architect / carpenter scales PROJECT DETAILS - Site notes + reference photos via PHPicker (no permission needed) - Stair-type-aware summary card POLISH - Custom fraction precision (1/2 to 1/64) - Multi-flight landing suggestions when over the regional flight cap - Animated How-to-Cut walkthrough in Reference Still 100% offline. No tracking, no accounts, no servers. Camera used only when you tap Measure.

Version 1.1.0

The developer, ZHENGQIAO JIANG, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    • ZHENGQIAO JIANG
    Size
    • 1.8 MB
    Category
    • Utilities
    Compatibility
    Requires iOS 17.0 or later.
    • iPhone
      Requires iOS 17.0 or later.
    • Mac
      Requires macOS 14.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    English and 5 more
    • English, French, German, Japanese, Korean, Spanish
    Age Rating
    4+
    In-App Purchases
    Yes
    • Lifetime $79.99
    • Yearly $29.99
    • Monthly $4.99
    • Weekly $1.99
    • Learn More
    Copyright
    • © Alex Jiang 2026
  • Developer Website
  • Privacy Policy

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